/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package com.sun.org.apache.xml.internal.security.transforms.implementations;

import java.io.OutputStream;

import com.sun.org.apache.xml.internal.security.c14n.CanonicalizationException;
import com.sun.org.apache.xml.internal.security.c14n.implementations.Canonicalizer20010315ExclOmitComments;
import com.sun.org.apache.xml.internal.security.exceptions.XMLSecurityException;
import com.sun.org.apache.xml.internal.security.signature.XMLSignatureInput;
import com.sun.org.apache.xml.internal.security.transforms.Transform;
import com.sun.org.apache.xml.internal.security.transforms.TransformSpi;
import com.sun.org.apache.xml.internal.security.transforms.Transforms;
import com.sun.org.apache.xml.internal.security.transforms.params.InclusiveNamespaces;
import com.sun.org.apache.xml.internal.security.utils.XMLUtils;
import org.w3c.dom.Element;

/**
 * Class TransformC14NExclusive
 */
public class TransformC14NExclusive extends TransformSpi {

  /**
   * Field implementedTransformURI
   */
  public static final String implementedTransformURI =
      Transforms.TRANSFORM_C14N_EXCL_OMIT_COMMENTS;

  /**
   * Method engineGetURI
   *
   * @inheritDoc
   */
  protected String engineGetURI() {
    return implementedTransformURI;
  }

  protected XMLSignatureInput enginePerformTransform(
      XMLSignatureInput input, OutputStream os, Transform transformObject
  ) throws CanonicalizationException {
    try {
      String inclusiveNamespaces = null;

      if (transformObject.length(
          InclusiveNamespaces.ExclusiveCanonicalizationNamespace,
          InclusiveNamespaces._TAG_EC_INCLUSIVENAMESPACES) == 1
          ) {
        Element inclusiveElement =
            XMLUtils.selectNode(
                transformObject.getElement().getFirstChild(),
                InclusiveNamespaces.ExclusiveCanonicalizationNamespace,
                InclusiveNamespaces._TAG_EC_INCLUSIVENAMESPACES,
                0
            );

        inclusiveNamespaces =
            new InclusiveNamespaces(
                inclusiveElement, transformObject.getBaseURI()).getInclusiveNamespaces();
      }

      Canonicalizer20010315ExclOmitComments c14n =
          new Canonicalizer20010315ExclOmitComments();
      if (os != null) {
        c14n.setWriter(os);
      }
      byte[] result = c14n.engineCanonicalize(input, inclusiveNamespaces);

      XMLSignatureInput output = new XMLSignatureInput(result);
      if (os != null) {
        output.setOutputStream(os);
      }
      return output;
    } catch (XMLSecurityException ex) {
      throw new CanonicalizationException("empty", ex);
    }
  }
}
